Siemens SIPROTEC 7SJ61, Manual, Page: 346 / 454

Technical Data
4.13 Ground Fault Protection 50N(s), 51N(s)
SIPROTEC, 7SJ61, Manual
C53000-G1140-C210-1, Release date 02.2008
346
4.13 Ground Fault Protection 50N(s), 51N(s)
Ground Fault Pickup for All Types of Ground Faults (Definite Time Curve)
Ground Fault Pickup for All Types of Ground Faults (Inverse Time Characteristic)
Ground Fault Pickup for All Types of Ground Faults (Inverse Time Characteristic Logarithmic inverse)
Pickup current 50Ns-2
for sensitive transformer
for normal 1-A transformer
for normal 5-A transformer
0.001 A to 1.500 A
0.05 A to 35.00 A
0.25 A to 175.00 A
Increments 0.001 A
Increments 0.01 A
Increments 0.05 A
Delay Time T
50N-2
0.00 s to 320.00 s or
∞
(disabled) Increments 0.01 s
Pickup current 50Ns-1
for sensitive transformer
for normal 1-A transformer
for normal 5-A transformer
0.001 A to 1.500 A
0.05 A to 35.00 A
0.25 A to 175.00 A
Increments 0.001 A
Increments 0.01 A
Increments 0.05 A
Delay Time T
50N-1
0.00 s to 320.00 s or
∞
(disabled) Increments 0.01 s
Dropout delay time 50Ns T DROP-OUT 0.00 s to 60.00 s Increments 0.01 s
Operating Time
≤
50 ms
Dropout ratio Approx. 0.95 for 50Ns-1 > 50 mA
Measurement Tolerance 2 % of setting value or 1 mA
Operating Time Tolerance 1 % of setting value or 20 ms
User-defined Curve (defined by a maximum of 20 value pairs of current and time delay)
Pickup Current 51Ns
for sensitive transformer
for normal 1-A transformer
for normal 5-A transformer
0.001 A to 1.400 A
0.05 A to 4.00 A
0.25 A to 20.00 A
Increments 0.001 A
Increments 0.01 A
Increments 0.05 A
Time multiplier T
51Ns
0.10 s to 4.00 s or
∞
(disabled) Increments 0.01 s
Pickup Threshold Approx. 1.10 · I
51Ns
Dropout ratio Approx. 1.05 · I
51Ns
for I
51Ns
> 50 mA
Measurement Tolerance 2 % of setting value or 1 mA
Operating Time Tolerance in Linear Range 7 % of reference value for 2
≤
I / I
51Ns
≤
20 + 2 % current toler-
ance, or 70 ms
Pickup Current 50Ns
For sensitive transformer
For normal 1-A transformer
For normal 5-A transformer
0.001 A to 1.400 A
0.05 A to 4.00 A
0.25 A to 20.00 A
Increments 0.001 A
Increments 0.01 A
Increments 0.05 A
Starting current factor 51Ns Startpoint 1.0 to 4.0 Increments 0.1
Time factor 51Ns TIME DIAL 0.05 s to 15.00 s;
∞
Increments 0.01 s
Maximum time 51Ns Tmax 0.00 s to 30.00 s Increments 0.01 s
Minimum time 51Ns Tmin 0.00 s to 30.00 s Increments 0.01 s
Characteristics see Figure 2-51
Tolerances
Times inv. 5 %
±
15 ms for 2
≤
I
/
I
51Ns
≤
20 and
51Ns TIME DIAL
≥
1 s
def. 1 % of setting value or 10 ms